Mesozoic era


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See also: Geologic Timescale (table)Geologic Timescale
Era Period Epoch Approximate duration
(millions of years)
Approximate number of years ago
(millions of years)

Cenozoic Quaternary Holocene 10,000 years ago to the present  
Pleistocene 2 .
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Mesozoic era

(mĕz'əzō`ĭk) [Gr.,=middle life], major division of geologic time (see Geologic TimescaleGeologic Timescale
Era Period Epoch Approximate duration
(millions of years)
Approximate number of years ago
(millions of years)

Cenozoic Quaternary Holocene 10,000 years ago to the present  
Pleistocene 2 .
..... Click the link for more information.
, table) from 65 to 225 million years ago. Great crustal disturbances that marked the close of the Paleozoic and the beginning of the Mesozoic eras brought about drastic changes in the topography of North America. The Appalachian geosyncline, or downward thrust of the earth's crust, was replaced by the Appalachian Mts., and the eastern part of the continent was elevated during most of the era. The Appalachians were subjected to erosion, the products of which were deposited along the Atlantic coast, which had become a lowland region, or in the ocean beyond. Aside from the Appalachians, the other dry (consistently) areas of the continent were the Canadian Shield, the Antilles areas, and a mountain range elevated in part of the Cordilleran geosyncline. The Mesozoic tectonic activity included numerous subduction zones, such as those along the Pacific margin of the supercontinent Pangaea. Later, Pangaea began to split into the supercontinents of Gondwanaland and Laurasia, and N Africa began to rift apart. By the late Mesozoic, tectonic activity increased dramatically: the new Indian Ocean began to open, the Atlantic Ocean began to open along an extensive rift zone separating the Americas from Europe and Africa (see seafloor spreadingseafloor spreading,
theory of lithospheric evolution that holds that the ocean floors are spreading outward from vast underwater ridges. First proposed in the early 1960s by the American geologist Harry H.
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). The life of the Mesozoic was dominated by the reptiles that evolved into the large land-dwelling dinosaurs of the Jurassic and Cretaceous periods. Flying reptiles and birds first appeared during the Mesozoic. Mammals probably evolved from some common ancestor of the reptiles early in the Triassic Period, but were subordinate to the reptiles until the end of the era, when the dominance of reptiles was ended by the extinction of the dinosaurs. Conifers dominated the plant life, with modern pines and sequoias first appearing. Flowering plants, deciduous trees, and grasses also appeared during this era.
References in periodicals archive ?
The observations made during the present investigation have brought out interesting details on the events recorded in the Indian sub-continent during the close of Mesozoic era.
The metaphorical portrayal of the dinosaur in the early 21st Century is much more violent and less secure than were the real dinosaurs of the Mesozoic era.
During the Mesozoic era and Cenozoic period, various metallic resources were formed by mineralisation related to the intrusion of volcanogenic and igneous rock.
It has been traditional, although at the same time simplistic and mistaken, to attribute the characteristics of present-day reptiles to the great reptiles of the Mesozoic Era.
This is part of the Mesozoic Era when dinosaurs roamed the Earth.
In their place they built a community of scholars working toward understanding and communicating what life was like millions of years ago in the Mesozoic era.
The narrow layer that contained the iridium was sixty-five million years old and was therefore right at the boundary where the Mesozoic era yields to the Cenozoic era.
It is better that capitalism has survived the Cold War, just as it was better that the mammals survived the Mesozoic era when dinosaurs became extinct.
The plot of Jurassic Park is based on the premise that insects in the Mesozoic era (230 million to 65 million years ago) must have frequently drawn blood from bolder creatures, like dinosaurs, for example.
Ginkgo biloba or maidenhair tree has fossil evidence dating back to the Mesozoic era or approximately 250 million years ago.
His predictions never come close to anything that happens on Planet Earth, and his ideological perspective is from the Mesozoic era.
The year was 1903 somewhere near the beginning of the end of journalism's Mesozoic Era when yellow was the color of choice and truth was too often considered an inconvenience.